Stockholders' Equity Dividends Declared (Details) - $ / shares	3 Months Ended		9 Months Ended
	Oct. 31, 2016	Oct. 31, 2015	Oct. 31, 2016	Oct. 31, 2015
Dividends [Abstract]
Common Stock, Dividends, Per Share, Declared	$ 0.45	$ 0.40	$ 1.30	$ 1.18